ipmi_ssif: remove redundant null check on array client->adapter->name

The null check on client->adapter->name is redundant as name is an
array of I2C_NAME_SIZE chars and hence can never be null. We may as
well remove this redundant check.

Detected by CoverityScan, CID#1375918 ("Array compared against 0")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>